Conventional topical creams and ointments carrying an active viricidal or microbicidal agent have employed a water-oil emulsion type formulation. Some of the disadvantages of such prior formulations are related to their greasy feeling, or the clothes staining ability, or to the ease in which they are inadvertently wiped off the affected area. The latter trait tends to decrease their effectiveness and the former traits tend to discourage users from using the same as often as medically advantageous.
A very important disadvantage in these prior art formulations is their effectiveness extends essentially only to the surface of the epidermis, except for any small portion which may contact an open wound or sore on the skin. These prior art formulations have very limited ability to penetrate through the pores of the epidermal layer to contact an infectious agent located below the surface of the epidermis.
Another disadvantage of prior oil/water emulsion type compositions, particularly with certain active agents such as povidone-iodine, is shorter shelf life. That is, the composition tends to separate or lose its homogenous character or interact with the active agent and decrease its intended effectiveness.
Therefore, prior to the present invention, there has been an unfulfilled need for a topical cream or ointment type composition carrying an active viricide and/or microbicide or the like, which does not possess the disadvantages noted above and which has the ability to deliver an effective concentration of the active ingredient to both the immediate surface area and penetrate beneath the surface area of the skin to enhance effectiveness of the active agent.